A study of the application of nmr spectroscopy, in particular C-13 nmr, to the conformational analysis of organic compounds is being made. The use of lanthanide shift reagents to determine the solution stereochemistry of conformationally flexible acyclic molecules is being explored. The use of optically active shift reagents to study the conformations and absolute configurations of optically active substrates is being examined. The relationships between spin-lattice relaxation times and conformations of acyclic molecules is being studied. Using C13, H1, and N15 nmr spectroscopy, the conformations and cation binding properties of small cyclic peptides is being studied. Variable temperature T1 measurements of cyclic hydrocarbons and acyclic alcohols are being made in an attempt to relate relaxation times and molecular conformation. BIBLIOGRAPHIC REFERENCES: K.L. Williamson and J.D. Roberts, "Conformational Analysis by NMR. C13 and N15 Spectra of Lactams", J. Amer. Chem. Soc., 98(1976) In Press. E. Rosenberg, K.L. Williamson and J.D. Roberts, N15 Nuclear Magnetic Resonance Spectroscopy. Natural Abundance N15 NMR of Monosubstituted Indoles", Organic Magnetic Resonance, 1976 In Press.